Why does economics need to be a science?

I've seen some commentary going around the blogosphere about this article by economist Raj Chetty, "Yes, Economics is a Science." I believe there is some merit to the question of whether or not (and what ways) economics is a science. But what's more striking to me is why the question continues to create such a stir.

So that's why I ask the question: what is it about being a "science" that makes us argue over it? My conjecture: modern mythology. Or more precisely, modern messianism.

Here is the messianic myth of the modern age. Once upon a time, we were living in darkness, plagued by superstitious beliefs to which we clung due to indoctrination by authorities. Then, around 400 years ago or so, a revolution was stirred, and science came to show us the light and brought us into a new age of progress. Now, if only we embrace science and reject whatever isn't science, we will continue along the path of enlightenment, so that one day we can all live in peace and prosperity.

The roles of good and evil here are played by understanding on the one hand and bias on the other. Anything which is "science" can help us understand, anything which is not can only obscure. That's why the battle over calling economics a science is so perilously important--if it isn't a science, then it is merely a tool to fuel ideological agendas. But a real science could never do such a thing.

If we reject this myth, then the question becomes less perilously important (though still interesting for other philosophical reasons). Science as we know it today has helped bring about many positive changes, but it is not going to bring about the kingdom of enlightenment. It may be worthwhile at some point to give an argument stating all the reasons why I think this, but my main argument goes something like this. Science, as understood today, is supposed to be objective, in the sense of separating the observer from his biases and forcing him to interpret the facts from a fresh point of view. The problem is that you can't build a better society on a model of separation. Things which could be construed as bias are actually some of the most essential attachments which hold civilization together: family, tradition, empathy, duty, and above all love.

An important corollary of rejecting the messianic myth of scientism: society will not heal itself by adopting the right policies at the level of federal government. If society were merely an object of scientific study, then I suppose it could be engineered to perfection. That is not the case.